I can’t tell if someone’s into me or just being nice when our dates end with “Let’s do this again”

Ever leave a date and hear “We should definitely do this again,” but by next week you’re circling back with no reply? I’ve been down that road too—someone laughs, leans in, even mirrors my energy… then I don’t hear from them again. Turns out body language experts say things like posture mirroring and vocal synchrony do signal rapport—but they don’t guarantee interest if the other person isn’t equally invested. So, here I am, stuck in text limbo: are they actually into me or just being politely curious? How do you distinguish genuine chemistry from “being nice” when all the nonverbal signals seem right—but the follow-up is ghosted?